1. Field of the Invention
The present invention relates to a connecting box for connecting connectors disposed at the end of a wire harness so as to branch the circuit.
2. Description of the Related Arts
The connecting box, for forming branch circuit, is used to connect the end of the wire harness with various electric devices by branching the circuit thereof so as to locate branching positions at one position to accomplish a reasonable and economical branch connection of the wiring. With very dense wiring in the wire harness, various types of connecting boxes have been developed. Normally, a plurality of connecting circuits are provided inside the casing of the connecting box and connecting openings for connecting connectors disposed at the ends of the wire harness are formed on an end face of the casing.
Various types of connecting circuits including the bus bar method have been proposed to form a highly dense circuit. According to a first example, a connecting circuit includes a plurality of bus bars formed in a maze configuration and pins disposed at the ends of the bus bars standing erect from the surface of the connecting circuit so as to connect connectors with the pins. According to a second example, a plurality of bus bars are provided in parallel with each other in a casing so as to be connected with each other at appropriate intervals by connecting terminals connected with connectors.
In the first example, however, the configurations of the connectors are varied because pins are placed at various positions. If the pins are so placed that the connectors in the same configuration can be used, there is a possibility that the connectors will be inserted into connecting openings erroneously. Thus, it is inevitable to use connectors in various configurations.
In the second example, the connectors and the bus bars are connected with each other in a complicated manner. Thus, it is impossible to connect a connector with a plurality of the same circuits and hence a highly dense and compact connecting circuit cannot be constructed.
Further, in the second example, in order to constitute the casing of a connecting box for, an upper casing and a lower casing are connected with each other by engagement between locking portions of the upper and lower casings, with bus bars interposed between the upper and lower casings.
However, the configuration of the upper casing and that of the lower casing are different from each other. Thus, it is necessary to prepare a mold for the upper casing and a mold for the lower casing, which leads to a high manufacturing cost. In addition, it is necessary to check whether the connecting box is an upward or downward facing connecting box.